Prevention and treatment of alcohol abuse is a significant research and public health priority. To date one of the most promising approaches for substance use reduction, contingency management (CM), has not been well studied with alcohol abusers. Contingency management interventions provide substance users with cash, vouchers, or some other reinforcer that is contingent upon a desired treatment goal. A primary reason that CM has not been widely studied as an alcohol treatment is that due the rapid metabolism of alcohol by the liver there has not been a reliable and feasible way to verify abstinence or drinking reductions. However, devices are now available that provide an indication of alcohol use based on the concentration of alcohol in perspiration. A transdermal sensor is worn close to the skin and can be monitored remotely, which makes it possible to immediately reinforce abstinence or reduction. The objective of this proposal is to study the initial efficacy of CM for reducing drinking among heavy drinkers who are willing to reduce or stop drinking. Following necessary adaptations to established procedural, data collection, and intervention components with group of 15 (Aim 1), we will conduct a small (N = 30) clinical trial in which we will compare a 3-week CM condition to yoked noncontingent reinforcement (NR) (Aim 2). Participants in CM will receive reinforcement that is contingent upon maintaining abstinence as measured by a transdermal alcohol monitor;participants in NR will receive yoked reinforcement that is not contingent on their transdermal alcohol levels. A project website will be used to collect daily records of drinking, provide feedback about detection of alcohol to participants, and provide reinforcers. Transdermal alcohol concentrations and self-report data will provide information about changes in drinking during the active phase of treatment, and a 1-month follow-up assessment will measure short-term post-intervention outcomes. Establishing these components and an initial effect size for CM are essential first steps in a program of research with CM and alcohol monitoring to treat alcohol misuse and dependence. Our eventual goal is to conduct larger clinical trials to more rigorously evaluate the short and long-term outcomes of CM with this and other high-risk drinking populations.